Changing AC expansion valve

[komichal]

Hi guys,
As I am troubleshooting some unpredictability of my AC, I will replace my AC pressure sensor. I will take it to the AC shop to make sure they evacuate the freon before doing this. Denso sensor is on it's way to me.

I am currently thinking about having them changed the expansion valve too, just to be sure that it is not the troublemaker. The new valve is is about 40 USD here (some FRIGAIR brand I never heard of) and it would make sense to change it all at once when the system is evacuated. by "All" I mean AC pressure sensor, expansion valve and probably the dryer too as it has never been changed in the past 10 years and it is actually a cheap thing.

So the guestion: can the expansion valve be changed just from the engine compartment or is there a need to dismount the dashboard too? The AC shop I go to does not have much experience with Yaris so I would not trust them with taking apart half of the car, you know.

Thanks